pearl mussel
noun
1- an elongated freshwater bivalve mollusc which occasionally produces small pearls, found in large rivers of the northern hemisphere珍珠贻贝, 珍珠蚌。
1.1
- Margaritifera margaritifera, family Margaritiferidae.拉丁名Margaritifera margaritifera,珍珠蚌科。